At that time the famous rules of Thatta, Noori Jam Tamachi was Unar. Originally Unar have been rulers fighters and lovers. On the origins of Sammat dynasty several theories have been put forward. They are believed their name from and are considered descendants of Sam (Shem), the eldest of the three surviving sons of the prophet Nuh (Noah). According to others they are the descendants of Sam, the son of Umar, son of Hashim, son of Abu Lahab, an uncle of the Islamic prophet Muhammad. Yet others believe Sam was the son of Umar, son of Akrama, son of Abu Jahal, the tormentor of Muhammad. Some argue that rulers used the title of Jam, than Sammas are also considered by some to be the descendants of Jamshid, the legendary king of Persia who could see in his wine cup (magical jams).
Jam Unar was the founder of Samma dynasty mentioned by Ibn Battuta, the famous travellor from North africa. Jam Unar, the Samma chief, taking advantage of the strained relation between Sumras (Soomra) and the Sultanate of Dehli, defeated the last Sumra rules, son of Dodo, and established Sammatt rulein 752/1351. Jam Banbhiniya had two sone Jam Unar (1333-1352) and Jam juna (1352-1368), than followed by Jam Tamachi, Jam UnarII, Jam Ali Sher, Jam Sanjar, Jam Nizamuddin I, Jam Nizam al Din II and Jam Firuz. From the other son Jam Juna it was followed by Jam Tohachi, Jam Kran, Jam Sikandar, Jam JuanII, Jam Fath, Jam Sikander II,Jam Salah al- Din. This is precisly the origin of Unars from Jam Unar the founder of the dynasty and Junejoes from Jam Juna the younger son. Today Unars are setteled in District Nawabshah, District Larkana, District Jacobabad and District Sanghar.